This invention relates generally to split vamp shoes and particularly to an improved stabilization system which counteracts lateral motion and enhances the pivot action between the vamp sections.
The first commercially successful split vamp shoe is disclosed in commonly owned U.S. Pat. No. 3,546,796. This shoe utilizes two sets of laces to provide independent adjustment of each vamp section and improve the flexible action of the sole. Later improvements disclosed in U.S. Pat. No. 4,200,998, and U.S. Pat. No. 4,538,367 and U.S. Patent Application Ser. No. 07/074,953 filed July 17, 1987, also commonly owned, provide means of utilizing a single continuous lace and yet maintaining the superior adjustment and flexibility of the split vamp concept.
The prior art discloses the use of heel tabs to increase lateral stability of the heel area. For example, U.S. Pat. No. 4,402,146 discloses an athletic shoe having heel tabs overlapping a conventional heel counter. The tabs are intended to extend only substantially to the limits of the heel area defined by the heel counter. In this shoe a wedge-shaped lift portion is disclosed between the outsole and the midsole which has a peripheral horseshoe shaped portion of hard material relative to the softer center portion. The purpose of the horseshoe shape is to cooperate with the heel tabs to resist bulging. While this arrangement provides a partial stiffening rim of relatively hard material, it is a relatively complicated and expensive system.
This invention overcomes the disadvantages noted and enhances the flexible quality of split vamp shoes in a manner not revealed in the known prior art.